Question { HCL, 38919 }

why earth hole size is biggest in plug point?

Answer

Earth is a big conductor if we are talking about the
conductivity so the theory is the bigger the size the
smaller the resistance so the earth itself serve as a
conducting path of the resistance to secure the lives and
safety of the properties if in case there is incidental and
transient fault of the power systems.

Question { Orpic, 7948 }

What is diffrents between preventive maint. and maintenance?

Answer

preventive maintenance is defined as maintenance activities
that cover all programmed services carried out to control
deteriorating conditions that lead to the occurrence of
failure while maintenance covers all undertaken activities
to keep equipment,machineries and facilities in a desired
state or condition all other services done to return the
equipment or facilities back to that desired condition,

Question { 9904 }

there are a transformer and a motor. both are connected to
3phase, 415 Volt, 50Hz power supply. Both are working with
induction principles. Then, why, motor is rotating and
transformer is not rotating.

Answer

it simply because the motor has rotating core.It rotates
only due to the attraction n repulsion of the induced
magnets around in the stator while the transformer have
stationary core only that provide stable and variable supply
through electromagnets.

Question { 8624 }

what is preventive maintenance

Answer

preventive maintenance is a maintenance activities that
cover all programmed services carried out to control
deteriorating conditions that lead to the occurrence of
failures.These activities must be performed before these
deteriorating conditions develop into a breakdown or
disturbance in production.

Question { 7769 }

why battery is connected in parallel ?

Answer

It simply because it improve the battery current sourcing
ability for minimum voltage drop.